The MeatEater Podcast

Episode 766: The Truth About Chronic Wasting Disease (CWD)
Host: Steven Rinella
Guests: Dr. Mike Chamberlain (Warnell School of Forestry, Univ. of Georgia), Dr. Mark Ruder (College of Veterinary Medicine, Univ. of Georgia)
Date: September 22, 2025

Episode Overview

This episode is a comprehensive deep dive into Chronic Wasting Disease (CWD), a fatal neurological disease affecting deer species across North America. Host Steven Rinella brings together leading wildlife disease experts Dr. Mike Chamberlain and Dr. Mark Ruder to unravel myths, break down the latest research, and pose hard questions about the future of deer populations, deer hunting, and wild game consumption. The conversation addresses controversies, scientific unknowns, and the long, slow timeline over which CWD impacts wildlife and hunting culture, especially in light of recent high-prevalence findings from the Arkansas study.

Key Discussion Points & Insights

1. Understanding CWD: What Is It and Why Does It Matter?

(Main segment starting at [10:45])

• CWD is a prion disease: Abnormal proteins (prions) misfold, accumulate in the brain, and are not broken down by the body, resulting in neurological damage and “holes” in brain tissue (spongiform pathology).
  • Dr. Chamberlain analogy: Folding a fitted bed sheet—when folded wrong, it doesn’t work; when right, it functions as intended ([14:22]).
• Prion diseases are not unique to deer: Humans can get Creutzfeldt-Jakob Disease, cattle can contract mad cow (BSE), and sheep get scrapie.
• No human has contracted CWD to date. Health advisories are precautionary since experience with similar prion diseases raises concern for unknown risks.

Notable Quote

“It’s a 100% fatal disease.”
—Dr. Chamberlain ([20:47])

2. Why Is There Controversy About CWD?

(Addressed throughout [21:04]–[26:51])

• Hunters' skepticism emerges from:
  • CWD’s prevalence in regions still boasting robust deer herds (“if it’s so bad, where are all the dying deer?”)
  • Frustration over management rules (“bait bans don’t make sense if deer socialize anyway”)
  • No documented human cases, but still advised not to eat positive deer
• Covid-19 comparisons: Both issues saw rapidly deployed, sometimes confusing, regulations without clear threats felt directly by everyone, leading to "we're done listening" attitudes ([26:16]).

Notable Quote

“We've hit a dangerous spot around CWD. A lot of guys are like, ‘I'm done.’ And I don’t think we should be done.”
—Steven Rinella ([26:32])

3. CWD Progression and Time Scale: Population & Individual Impacts

(Main discussion [31:59]–[39:36], [44:06], [54:00])

• CWD doesn’t “crash” populations right away: It manifests slowly—decades before visible effects emerge.
• Prevalence curve:
  • Can hover at low levels (1–2%) for years, but then elevates, sometimes exponentially.
  • Populations may appear normal even as CWD builds, then suddenly shift to high infection/mortality rates.
• Contrast with “fast” deer diseases: EHD (hemorrhagic disease/blue tongue) kills rapidly and visibly; CWD operates slowly and cryptically.
• Survival statistics:
  • CWD+ does: 60% annual survival vs. 80% CWD–
  • CWD+ bucks: 40% vs. 70% ([79:17]–[80:03])
• Direct CWD mortality: About 20% of annual deaths in heavily affected populations are directly from the disease ([81:12]).

Notable Quote

“There are examples now of when we're at the end of that [prevalence] curve, like when we're decades down the road, we have glimpses into what that picture looks like.”
—Mark Ruder ([43:00])

4. What Management Works—and Where?

(Key section [44:06]–[50:12], revisited [97:31])

• Toolbox approach: Carcass movement bans, bait bans, culling, etc. are sometimes effective, but only when applied early and aggressively.
• Victories are rare, but real:
  • New York successfully eradicated an early outbreak by rapid, aggressive action ([45:48]–[47:08]).
  • When detections come late, containment is no longer realistic and management shifts to “living with CWD.”
• Definition of success changes:
  • Early: eradicate or contain
  • Endemic: keep prevalence as low as possible, accept new “normal” population levels

Notable Quote

“...the populations are so far along... when you get up to 50%, your management options have changed. You're now thinking about the future sustainability of the population.”
—Dr. Chamberlain ([98:10])

5. Arkansas Case Study: What Does a CWD Epidemic Look Like?

(Major findings presented [63:36]–[80:00])

• Arkansas, 2025:
  • Prevalence among mature bucks: 68%
  • Mature does: ~35%
  • Buck age structure “crashes”—hard to find 5+ year-old bucks
  • Population is declining at about 13–14% per year ([95:54])
• Field study involved:
  • GPS collaring, tracking, sampling
  • Both field and lab necropsy
  • Behavioral shifts in infected animals—less vigilance, odd movement, in some cases, more interaction with other CWD+ deer ([75:59])
• Frightening “new normal”:
  • 1–5 deer per square mile in high prevalence zones ([118:56])
  • Some areas with “you can’t find deer” ([119:02])

Notable Quote

“You can't find deer. You can drive around at night, you don't see deer...You're gonna get to some point where the population is going to stabilize…but it's not going back to where it was.”
—Dr. Chamberlain ([119:02])

6. Future Outlooks, Uncertainties, and Hard Truths

(Scattered throughout, main wrap-up [140:39]–[157:55])

• CWD-resistant deer:
  • Some genotypes may delay CWD progression but not confer true resistance ([107:48]); genetic solutions are not imminent or straightforward.
  • Releasing "resistant" deer from game farms is controversial and possibly counterproductive ([115:53]).
• Is “do nothing” viable?
  • No: inaction will, over decades, lead to higher prevalence, expanded footprint, and lower deer herds ([129:34], [132:02]).
• “New normal” in high CWD areas:
  • Enduring lower densities, fewer mature bucks, and ongoing risk/uncertainty for hunters and managers
• No “silver bullet”:
  • All current management options are imperfect; efforts are aimed simply at slowing progression (“shroud of prevention beats shroud of reaction” – [154:55])
• Hunters' burdens:
  • Uncertainty over food safety (none of the experts will eat a burger made from CWD+ deer—[143:27])
  • Adapting cherished hunting traditions and land management dreams to new biological realities

Notable Quotes

“If you’re in an area with low prevalence... your best chance of keeping what you have is to keep prevalence low and to keep it out entirely.”
—Dr. Chamberlain ([156:36])

“The fight shouldn’t start when you find your first case. The fight should start before you find your first case.”
—Steven Rinella ([155:02])

“There’s a lot we don’t know about chronic wasting disease.”
—Mark Ruder ([134:15])

Notable Quotes & Moments (with Timestamps)

• “[CWD is] a 100% fatal disease.” —Dr. Chamberlain ([20:47])
• “We've hit a dangerous spot around conversations about CWD. A lot of guys are like, ‘I'm done.’ And I don’t think we should be done.” —Steven Rinella ([26:32])
• “About 20% of all mortalities were linked directly to CWD. That’s in addition to predation and harvest...” —Dr. Chamberlain ([81:12])
• “The more you can keep [prevalence] suppressed, the more you suppress the very negative consequences at the population level.” —Mark Ruder ([49:55])
• “No, I wouldn't eat that burger [made from five CWD-positive deer].” —Dr. Chamberlain and Mark Ruder ([143:27])
• “I don’t expect you to listen to this and change everything you think…but if you just think carefully... this is a problem that is not going to just go away.” —Dr. Chamberlain ([156:36])

Timestamps for Important Segments

• [10:45] — What CWD is, prion explanation
• [20:47] — Disease fatality clarified
• [26:32] — Reasons for hunter skepticism and “done” attitudes
• [31:59] — Discussion of timescale and prevalence curve
• [44:06] — Have management strategies ever worked?
• [63:36] — Arkansas study findings, age structure crash, population decline
• [79:17] — Survival statistics for CWD+ and negative deer
• [95:54] — Population now declining 13–14%/year
• [118:56] — Deer densities plummet to 1–5/sq mile in high prevalence Arkansas
• [140:39] — Efforts to manipulate the “new normal”
• [143:27] — Host/guest responses to the CWD+ burger challenge
• [155:02] — Prevention vs reaction
• [156:36] — Message to hunters: prevention, engagement, and context

Key Takeaways (“At-Home Lessons” for Hunters)

• Prevention is crucial. If your area’s prevalence is low, support aggressive management and surveillance.
• CWD’s impact is slow and often invisible until suddenly it’s severe and irreversible.
• “Success” in CWD management is relative—early stages can be contained; later stages require learning to live with chronic disease and altered deer populations.
• Testing your deer and complying with agency recommendations are vital to preserve herd health and future hunting.
• There are no risk-free shortcuts, and no agency, researcher, or listener can wish the problem away.
• Accept uncertainty. Scientists are working with limited data, evolving understanding, and an infuriatingly complex disease.

Final Thoughts

This episode underscores that CWD is a slow-building crisis for both wildlife and hunting culture. Rinella and guests urge listeners to cling to prevention, stay informed, and push for better research funding—because the uncomfortable reality is that “the fight shouldn’t start when you find your first case.” Hunters, landowners, and managers must act early, stick together, and resist the lure of denial if deer herds, hunting tradition, and wild venison are to survive for future generations.